頁籤選單縮合
題名 | 檳榔樹冠對降雨沖蝕能量之影響=The Effect of Betel Nut Canopy on Rainfall Erosion Energy |
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作者 | 吳輝龍; 張文詔; 吳嘉俊; 徐森雄; Wu, Huei-long; Chang, Wen-jaur; Wu, Chia-chun; Hsu, Sen-hsiung; |
期刊 | 中華水土保持學報 |
出版日期 | 19970300 |
卷期 | 28:1 1997.03[民86.03] |
頁次 | 頁33-46 |
分類號 | 434.273 |
語文 | chi |
關鍵詞 | 檳榔; 樹冠; CC次因子; Betel nut; Canopy; CC subfactor; |
中文摘要 | 檳榔是本省中南部坡地特有作物之一。由於檳榔樹冠形狀,覆蓋面積等特性相當一致,不會因樹齡增長有太多改變,所以適合作為探討喬灌木類植生樹冠對降雨沖蝕動能影響之先驅樹種。本研究之目的是將檳榔樹冠對降雨沖蝕力之影響加以量化,以為估算本土作物因子C之張本。受測檳榔樹之幹流率介於 30 % ∼ 85 % 之間,樹冠滴落水滴中值粒徑為 4.7 mm。檳榔 CC 值隨樹冠高度增加而增大,但隨降雨強度增加而減少。 所以檳榔在高降雨強度時遮蔽阻絕降雨能量之效果要比低降雨強度時為佳。檳榔樹冠高達某一程度後,於低降雨強度時其 CC 值會大於 1,顯然在此情況下檳榔樹冠對地表土壤沖蝕現象會有負面效果。 而且 RUSLE 中所使用之 CC 值估算公式並不適用於檳榔樹。本研究根據理論與實測數據推導出檳榔 CC 值估算公式 CC = 0.746 X DVR X H X 1 本公式型式精簡立論嚴謹,且由實測推求各項係數,使公式具有相當高之實用性,應可做為進一步推算本省作物因子 C 之基礎。 |
英文摘要 | Betel nut has been planted extensively in the mountain area middle and southern parts of Taiwan. the canopy shape and coverage of betel nut are quite unchanged with the change of canopy height. Hence, betel nut can be considered a pioneer plant in terms of examining the canopy effect of tree or bush on rainfall erosion energy. This study aims to quantify the betel nut canopy effect on rainfall erosion energy. the results derived from this study are taken as a base fro estimating C factor of domestic plant. Measured values of betel nut stem flow rate were between 30 % ∼ 85 %. Mean volumetric dimeter of droplet that dripped from betel nut canopy was 4.7 mm. Canopy cover subfactor of betel nut increases as canopy height increases, yet decreases as rainfall intensity increases. As a result, betel nut canopy cover appears to yield better protection against erosion for high rather then low intensity rains. Values of betel nut CC subfactor at low intensity rain can be greater than 1 as canopy height reaches to a certain level. This implies that effect of betel nut canopy cover against soil erosion can be negative. Also, the equation for calculating CC subfactor in RUSLE can no longer be applied for betel nut. An equation for calculating CC subfactor of betel nut was obtained (i. e. CC=0.746X DVR X H X 1 ) The equation, based on solid theory derivation and measured data regression, has a simple formation and practical nature that can be regarded as a solid base for estimating C factor of domestic plants. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。